Brahamaputra Basin

Brahamaputra Basin
toward north-east and altitudinal range of 900 m -2100 m covering part of Naga Hills.Beyond
this, the height again decreases to less than 900 m in the western part of Tirap and Lohit
districts. But the eastern part of Lohit, Tirap and Changlang distrcts are marked with steep rise in
the altitude 3000-4000 m range. In the Nagaland, the Barail range, piercing from south-west via
North Cachar, runs upto Kohima with its highest peak, Japavo (2,970 m) lying to the south of the
town.
Table.3 is showing the elevation variation in the Brahmaputra basin. The elevation information of
the entire Brahmaputra basin has derived from the Digital Elevation Model (DEM) data of Shuttle
Radar Topography Mission (SRTM) with spatial resolution 90 m (Map 3).
The lowest elevation observed near Dhubri, where the Brahmaputra River turns south and enters
Bangladesh. Highest elevation of 8401 m is found in this basin. Maximum area of the plain region of
the Brahmaputra valley falls under the 10-50 and 50 -100 m elevation range.
Table 3. Elevation zones
Sl. No. Elevation (m) Area (Sq.km) % of Total Area
1 10-50 12652.13 6.51
2 50-100 33336.92 17.15
3 100-200 27506.95 14.15
4 200-300 9395.54 4.83
5 300-400 6830.18 3.51
6 400-500 5632.02 2.90
7 500-750 12474.23 6.42
8 750-1000 11422.02 5.88
9 1000-1500 17728.88 9.12
10 1500-2000 13803.78 7.10
11 2000-3000 19510.02 10.04
12 3000-4000 14454.62 7.44
13 4000-5000 7697.08 3.96
14 5000-6000 1795.26 0.92
15 6000< 173.36 0.09
Source: SRTM DEM
9